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June 28, 1955 .1. K. ELDERKIN ELECTRODE FEED CONTROL 2 Sheets-Sheet 1 Original Filed Aug. 24, 1946 A 2% a w. E I up m M 4 T n m H l 5 ILF- .0.0 U h] nufl 4 a 1 M j 5 M 0.. w 3 4 g 3], N n W, 0. H h 7 J Tltii.

INVENTOR. JAMES K.ELDERKIN BY My? ,gg

ATTORNEY June 28, 1955 J. K. ELDERKIN,

ELECTRODE FEED CONTROL 2 SheetsSheet 2 Original Filed Aug. 24, 1946 Y .m m M R T R 0 mm T V L T m Kf S v E M A J V. B

nited States Patent ELECTRGDE FEED CONTROL James K. Elderkin, It'ionteiair, N. J., assignor of one-half to Joseph J. Mascneh, Maplewood, N. J.

Original application August 24, 1946, Serial No. 692,852, now Patent No. 2,571,552, dated October 16, 1951. Divided and this application October 2, 1951, Serial No. 249,353

4 Claims. (CL 314--52) This invention relates to are lamps, and particularly to the control of the forward motion or feed, of each of a pair of carbon electrodes, to maintain the burning tips of said electrodes within the same arcing distance, one of the other, and thus assure constancy of illumination in the area to be lighted.

An object of the invention is to provide carbon electrode feed control mechanism that is capable of maintaining constant feeding rates for each of the two electrodes; the feeding rate for one bearing a constant ratio to the feeding rate of the other, and each feeding rate being pre-selected to correspond to the established rate of consumption for the particular type of carbon electrode whose operation is to be controlled.

A second object of the invention is to provide a carbon electrode feed control operative upon a feeding mechanism to impart energizing impulses thereto at evenly spaced and regularly recurring time intervals of equal duration.

A third object is to provide two such feed controls, each operative upon its respective feeding mechanism to impart energizing impulses thereto at a rate which bears a constant ratio to the rate of energization of the companion feeding mechanism.

This application is a division of application Ser. No. 692,852, now Patent No. 2,57l,552, October 16, 1951, filed jointly by Frank I. Strassner and myself on August 24, 1946.

The accompanying drawings illustrate one only of the forms in which the invention may be embodied, and the ensuing description refers to the details and mode of operation of the illustrated embodiment. Other embodiments, of course, are embraced herein, insofar as they may follow the principles herein disclosed.

In the drawings:

Fig. 1 is a top plan view of an electrode feeding mechanism embodying my invention,

Fig. 2 is an elevational view thereof, taken on line 22 of Fig. 1,

Fig. 3 is a fragmentary, enlarged, vertical elevational view, taken on line 33 of Fig. 2,

Fig. 4 is a perspective view of an electrode feeding mechanism embodying the invention,

Fig. 5 is a diagrammatic view of the timing means which may be used for the control of the solenoid circuit of the invention, and

Fig. 6 is an enlarged fragmentary view thereof, showing the clutch members which are controlled by the governor in their disengaged position responsive to decrease in speed of the governor, said clutch members being part of a timing means which may be used in connection with the invention.

The operation of the mechanism embodying the invention shown in the drawings is as follows: A threaded feed screw 20 carries a suitable carbon holder or carrier 12. Said worm screw 20 has a ratchet wheel 24 keyed thereto and driven by a pawl 26 adapted to turn the ratchet wheel as the pawl is pulled forward. The feed pawl 26 is attached to a solenoid plunger acting against a spring so that, on the plunger being drawn forward, the pawl 26 rotates the ratchet wheel 24 (and thus the feed screw 20) a portion of one revolution.

It is apparent then, that each time the solenoid is energized, the worm 20 is rotated through a predetermined number of degrees, then when the solenoid is deenergized the spring forces the pawl back to its original position on the ratchet wheel and the next impulse of current will again rotate the worm as before. Thus. by feeding the solenoid with timed impulses of current, rotation of the worm feed screw can be timed with the impulses.

Most modern arc lamps require ditferent speeds for the positive and the negative carbon electrodes as the rate of consumption of the electrodes is often not uniformfor example, the rate of consumption of the positive carbon is in many cases as much as three to one with respect to that of the negative.

By the means hereinafter more fully explained, it will readily be seen that, using two exact mechanisms, one for the positive carbon and the other for the negative carbon embodying the invention, the feeding speed of each can be independently timed by merely changing the number of impulses per minute of the respective solenoids.

Any desired or convenient timing means may be associated with the said solenoid to impart impulses thereto at predetermined time intervals. Such timing devices may assume the form of any desired or conventional timing devices, such as those available on the open market. Or they may assume the form shown in Figs. 5 and 6, wherein the timing device comprises essentially a centrifugal force governor. The clutch members 72, 73 engage and disengage at predetermined time intervals as shown in Figs. 5 and 6 to open and close the circuit which energizes the solenoid, thus timing the same.

A structure embodying the invention is shown in Fig. l as comprising a carrier 12 having bearings 14 to slidably receive the guide rods 15, 16 which are fixed at opposite ends, in the brackets 17 and 18. Said carrier is further provided with an internally threaded bearing 19 for threaded engagement with the feed screw 20, said feed screw being rotatably journalled in said brackets. A source of current 21, such as an electric cable, is connected with the carrier 12 for the electrode 10, the carrier being preferably provided with insulation means to insulate the same from the bearing portion of the carrier. Such insulation means are generally designated by the numeral 22 and may assume any desired or convenient form. The inner end of feed screw 20 passes through the bracket 17 and has a collar 25 fixed thereto, said collar abutting the bracket 17. Beyond the collar 25 the extended end 23 of the feed screw 20 has a ratchet wheel 24 keyed thereto, as for example, by means of the hub 24'. On rotation of the ratchet wheel 24, electrode 10 will thus be advanced toward the complementary electrode 11 and bracket 18. The ratchet wheel 24 is rotated by a pawl 26 which is pivoted as at 27 to one end of a link 28, the other end of the link being pivoted as at 29 to a crank arm 38 keyed to the rock shaft 32, the latter being journalled in the U-shaped bearing 33 (see Fig. 3). A second crank arm 34 is fixed to the other end of the rock shaft, said arm 34 having a pin 36 projecting therefrom, said pin being received in a channel 36 defined by the flanges 37, 37' of the collar 38. The collar 38 is provided with a hub 49 keyed to the shaft 56 which is journalled in a bearing plate 51, said hub being maintained normally against the plate 51 under tension by the spring 52 on shaft 53 intermediate a second hub 49 of the collar 33 and the hearing plate 54. Collar 38 is slidably keyed to shaft 53 by pin 55 on said shaft received in slot 56 of hub 49' of the collar. The shaft 53 normally protrudes only partially into the collar. 38 (see Fig. 1). The carrier 12 may be returned to its starting position after the carrier has advanced to the end of the feed screw 2%) adjacent the bracket 18 on consumption of the electrode 19 as follows: A handwheel 57, keyed to the outer end of the shaft 51) is shifted manually toward the bracket 53. against the tension of the spring 52, said shifting motion being translated through the collar 33, pin 35 and crank arms 34 and 30, to the link 28, which is thus moved toward the handwheel 57, moving pivoted end 27 of pawl 26 with it and thus withdrawing the toothed end 39 of said pawl from the ratchet wheel 24.

The handwheel 57 is then rotated, rotating gear 55: keyed to the inner end of the shaft 53 and which meshes with the pinion 59 keyed to the extended end 23 of the feed screw Zil, thereby rotating said feed screw to return the carrier 12 to its original position adjacent the plate 17. By the arrangement described the link 23 is normally held under tension (spring '2, etc.) in the position shown in Fig. 2 to serve as a pivot bearing 27 for the pawl 26 to cooperate in the operation of the pawl and ratchet wheel.

In operation of the device, to advance the electrode toward the electrode 11 at a predetermined rate, the

solenoid 41 may be energized by a source of current i .1

which is indicated by the conventional plus and minus 0 symbols in Fig. 5. Any suitable means may be cut into said circuit to provide for the regulated periodic impulses of said solenoid.

In the form shown in Figs. 5 and 6, and previously referred to, the timing device comprises a governor 6i) driven by a motor 61. through the medium of gears 62, 63. One-half of the governor is fixed to the shaft S rotated by said gears, the other half thereof being fixed to stub shaft "71 which has fixed to the end thereof 1 a clutch member 72. The stub shaft 71 passes through the bearing 74) of a contact wheel 65' which has fixed thereto a clutch member 73 adapted to be engaged by the clutch member 72- of stub shaft 71. When the governor is rotated without the load of clutch member 73 and rotating switch member 65 to which member 73 is fixed, responsive to centrifugal force, the governor will draw the stub shaft 71 toward the shaft S thereby removing the clutch member 72 into engagement with the clutch member '73, thereby rotating switch member 65, imposing a load which slows down the governor to disengage the clutch parts-see Fig. 6. The switch member 65 carries one or more pair of contacts 66, 67 on its periphery, each pair of contacts being peripherally diametrically opposed so that once in each revolution of the member 65, each pair of contacts will having wiping engagement with the fixed contacts 68, 69 of the circuit.

In the operation of the device, the toothed end 39 of the pawl 26 engages the ratchet wheel 24 as shown in Fig. 2. The plunger 4t) of the solenoid 41 is reciprocated as indicated by the arrow 42 once responsive to each completion of the circuit through said solenoid.

The solenoid is provided with the conventional windings W around plunger 40. At one end, the plunger 40 is provided with a bumper or stop member 43 which may be of resilient material and which may be fixed thereto in any desired or convenient manner as by bolting the same thereto. Adjacent its other end, the plunger has a stub collar 44 fixed thereto. The end 45 of the plunger is bifurcated and is connected to the pawl 26 by pivot pin 46, a spring 47 bearing against or being fixed, at opposite ends to the pin 46 and a pin 29 on pawl 26 to normally urge the latter into engagement with the ratchet wheel 24.

In the form of invention shown in Fig. 4, each of the electrodes 10 and 11 is provided with its independent carrier and associated parts; rotation of the feed screws which engage said carriers to move the same, is timed by the solenoid and associated parts, for such electrode. This form of invention is especially adapted for those applications where, either because of differing rates of consumption or electrodes or for some other reasons, it becomes desirable to advance the same toward each other at diiferent rates of speed or by separate mechanisms.

The solenoid pawl and ratchet mechanisms for electrode 11 in the form shown in Fig. 4 are duplicates of the corresponding parts for electrode 10 and are designated by similar reference characters, primed for the purpose of distinction.

What I claim is:

1. In an arc lamp having two electrodes across Whose tips a current passes to produce an illuminating are, means associated with each electrode for independently moving said electrode relative to the other electrode, and separate means for energizing each of said moving means at repetitive rates bearing a constant ratio, one to the other, corresponding to the respective consumption rates for the two electrodes.

2. A mechanism as defined in claim 1, wherein said each of said separate energizing means operates at regularly recurring intervals of equal duration, and independently of voltage conditions across said electrodes.

3. A mechanism as defined in claim 1, wherein each of said separate energizing means includes an electric circuit having a rotary switch and motor-driven clutch means for rotating said switch during successive periods separated by equal time intervals.

4. In combination with an electrode carriage, means for imparting electrode feeding impulses to said carriage, means to maintain a constant frequency of energization of said impulsing means throughout the range of travel of said carriage, said last-named means including an electric circuit having a rotary switch, clutch means for rotating said switch during successive periods separated by equal time intervals, and means for disengaging said clutch means at regularly recurring time intervals of equal distinction.

Strong May 30, 1939 Elderkin et al. Oct. 16, 1951 

